Ed Murray/The Star-LedgerLuis Rivera was asked to step down after he signed a letter criticizing Newark Police Director Garry McCarthy, above, without union consent.

NEWARK — The president of a large Newark officers’ association was forced to resign this week after joining an attack on Police Director Garry McCarthy.

Luis Rivera, president of the Hispanic Law Enforcement Society of Essex County, stepped down after he signed a letter that was presented to the city council last week, expressing "no confidence" in McCarthy. The letter was read into the record by South Ward Councilman Ras Baraka as part of a motion to remove McCarthy from office, just two months after he was reconfirmed as director of the state’s largest municipal police department.

Rivera apparently signed the letter without the consent of the union.

"Mr. Rivera contributed his signature to the letter without consulting the Executive Board or its members," wrote Rosa Carter, the group’s vice president, in a letter received by the council yesterday. "Due to Mr. Rivera’s failure to consult with the Executive Board ... he has decided to voluntarily resign."

Rivera could not be reached for comment.

Aurelio Silva, president of the Portuguese American Police Association and Levi Holmes, president of the Bronze Shields also signed the letter. The three associations do not have formal negotiating powers but they represent many of the Hispanic, Portuguese and African-American officers that comprise roughly 80 percent of the department. It was unclear if Holmes and Silva had consulted their executive boards as well, as only their names appear on the letter.

Baraka, a longtime critic of McCarthy, used the letter in support of his effort to recall the police director. The motion failed after garnering only three votes from the nine-member council.